The Tropics are Growing Restless!

The GOES [Geostationary]  satellite  over the eastern USA captured an image of a rather large region of disturbed weather covering some 2.5 million square kilometers over the central Atlantic ocean just southeast of Bermuda and northeast of the Virgin Islands.  With so much extreme weather activity causing tornado and flood damage in several states over the past couple of days and capturing our collective attention, it’s been easy to forget that with the advent of spring the waters north of the equator have warmed considerably over the past 30 – 60 days, and  we are seeing more and more signs that the tropics are growing restless as we the “official” start of the 2011 Atlantic hurricane season is less that six weeks away.

 

Color-enhanced infrared GOES satellite image [NOAA] on 20 April 2011 showing what could well be the first ‘salvo’ of the 2011 Atlantic Hurricane Season.Satellite imagery, such as the color-enhanced infrared GOES satellite photo taken earlier this afternoon of 20 April 2011, clearly show a region of low pressure over the central north Atlantic  where rain and storm activity are being generated over a large area while the system moves in a generally westward direction.  This satellite image also shows the areas of extreme weather that have been attacking large regions of the USA, causing death and damage over the last couple of days. Also shown are areas of storm activity over northern South America, Panama and Central America. These are all signs that as surface waters and the atmosphere to the north of the equator continue to warm up  as spring takes hold of the northern hemisphere, tropical cyclogenesis can not be too far off even if the start of the “official” 2011 Atlantic hurricane season is 5-/12 weeks away. Other signs of impending tropical cyclonic activity and potential contributos to the same can be seen on other satellite images such as the ones that follow:

Full Earth disk composite satellite image of the western hemisphere on 20 April 2011. The full Earth’s disk satellite image [NASA] on the left show once again the “belt” of tropical activity girdling the Earth around the equator as it slowly migrates northward. On the eastern [far right] extreme of the “belt” there are alreday signs of tropical waves emerging from over equatorial Africa over the eastern Atlantic to the south of the Cape Verde islands. So, here we see the outline of what is generally known as “hurricane alley”, lots of tropical activity near the equator, “pulses” of tropical waves moving westward over equatorial Africa toward the eastern Atlantic, and to top it all off, a large region of low pressure and disturbed weather in the middle of the Atlantic. It is clear the tropics are growing restless and tropical cyclones can not be too far off. Not seen here, but shown in additional images below, are the increasingly warmer waters of the Atlantic, Caribbean, Gulf and eastern Pacific, and the lingering La Nina [ENSO] off the coast of Peru, which are all potential contributign factors to cyclogenesis in the Atlantic in 2011.Map of sea surface temperatures on 19 April 2011.

This satellite-based [NOAA] temperature map of sea surface waters on 19 April 2011, already shows surface waters at or above 30 Celsius along “hurricane alley”, parts of the Caribbean and the Gulf and also off Central America and Mexico in the eastern Pacific. Also shown are the much cooler waters of the coast of Peru indicating the lingering effects of the La Nina event that was active in 2010.

Soon, during the National Hurricane Conference and the soon to follow Florida Governor’s Hurricane Conference both NOAA National Hurricane Center and the folks at Colorado State University will issue their predictions for tropical cyclone activity in the North Atlantic basin for 2011 and then Mother Nature will do what it pleases and humankind will be divided into suffering bystanders or active participants who manage their risk and mitigate the impacts of hurricanes in their own communities.

For starters there is that large glub of disturbed weather over the central north Atlantic, which may develop further or just blow over, but which nevertheless warrants close monitoring. Then we already have the ‘belt’ of tropical activity circling the globe around the equator, the initial waves of storms coming over equatorial Africa toward the eastern Atlantic and “hurricane alley”, increasingly warmer surface waters in the Atlantic, Caribbean, Gulf and eastern Atlantic, and weakened but still lingering La Nina event off the coast of Peru. So many of the potential triggers or contributors to cyclogenesis in the Atlantic and eastern Pacific basins are already in place or being assembled. Let us see what Mother Nature has in store for us. Let us pay attention. Be prepared! MITIGATE!!